[PATCH 6/6] PCI: generic: Allow bus default MSI controller to be specified.

From: David Daney
Date: Fri Sep 11 2015 - 19:22:58 EST


From: David Daney <david.daney@xxxxxxxxxx>

If the device tree node for the bus has a "msi-parent" property, use
that as the default MSI controller for devices on the bus. Add device
tree binding documentation describing the new property.

This allows the pci-host-generic driver to be used in systems with
multiple MSI controllers.

Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
---
.../devicetree/bindings/pci/host-generic-pci.txt | 5 +++++
drivers/pci/host/pci-host-generic.c | 15 +++++++++++++--
2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/host-generic-pci.txt b/Documentation/devicetree/bindings/pci/host-generic-pci.txt
index cf3e205..daa6942 100644
--- a/Documentation/devicetree/bindings/pci/host-generic-pci.txt
+++ b/Documentation/devicetree/bindings/pci/host-generic-pci.txt
@@ -29,6 +29,11 @@ Properties of the host controller node:
to indicate the range of bus numbers for this controller.
If absent, defaults to <0 255> (i.e. all buses).

+- msi-parent : Optional property to indicate the MSI controller associated
+ with devices on the bus. If not present, the default MSI
+ controller is used. This property is further discussed in
+ interrupt-controller/msi.txt
+
- #address-cells : Must be 3.

- #size-cells : Must be 2.
diff --git a/drivers/pci/host/pci-host-generic.c b/drivers/pci/host/pci-host-generic.c
index 8219c0b..e0248b4 100644
--- a/drivers/pci/host/pci-host-generic.c
+++ b/drivers/pci/host/pci-host-generic.c
@@ -225,6 +225,7 @@ static int gen_pci_probe(struct platform_device *pdev)
struct device_node *np = dev->of_node;
struct gen_pci *pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
struct pci_bus *bus, *child;
+ struct msi_controller *msi;

if (!pci)
return -ENOMEM;
@@ -265,8 +266,18 @@ static int gen_pci_probe(struct platform_device *pdev)
if (!pci_has_flag(PCI_PROBE_ONLY))
pci_add_flags(PCI_REASSIGN_ALL_RSRC | PCI_REASSIGN_ALL_BUS);

- bus = pci_scan_root_bus(dev, pci->cfg.bus_range->start,
- &pci->cfg.ops.ops, pci, &pci->resources);
+ msi = NULL;
+ if (IS_ENABLED(CONFIG_PCI_MSI)) {
+ struct device_node *msi_node;
+
+ msi_node = of_parse_phandle(np, "msi-parent", 0);
+ if (msi_node)
+ msi = of_pci_find_msi_chip_by_node(msi_node);
+ }
+
+ bus = pci_scan_root_bus_msi(dev, pci->cfg.bus_range->start,
+ &pci->cfg.ops.ops, pci, &pci->resources,
+ msi);
if (!bus) {
dev_err(dev, "Scanning rootbus failed");
return -ENODEV;
--
1.7.11.7

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/